“If accurate, the prime minister’s chief adviser appears to have breached the lockdown rules. The government’s guidance was very clear: stay at home and no non-essential travel,” a spokesman stated.

“The British people do not expect there to be one rule for them and another rule for Dominic Cummings.”

The Scottish Nationwide Celebration’s Westminster chief Ian Blackford stated Mr Cummings ought to resign or be dismissed by Boris Johnson and that it was a “key test of leadership” for the PM.

And Ed Davey, performing chief of the Liberal Democrats, added: “If Dominic Cummings has broken the guidelines he will have to resign, it is as simple as that.”

No 10 declined to touch upon Friday evening.

The Mirror and the Guardian reported Mr Cummings, the previous Vote Go away chief who was the architect of the PM’s Brexit technique, had been approached by the police.

Durham Constabulary stated: “On Tuesday, March 31, our officers were made aware of reports that an individual had travelled from London to Durham and was present at an address in the city.

“Officers made contact with the house owners of that handle who confirmed that the person in query was current and was self-isolating in a part of the home.

“In line with national policing guidance, officers explained to the family the guidelines around self-isolation and reiterated the appropriate advice around essential travel.”

‘Keep at home’

Authorities recommendation on 31 March was for the general public to remain at home and solely depart their handle for clearly outlined causes, together with to train, important purchasing or for medical wants.

On the time – and as stays the case – these with signs of coronavirus are instructed to self-isolate at home and never depart even for important provides, if attainable, for seven days.

The supply near Mr Cummings stated he had not been spoken to by police, and that he had made the journey as a result of his mother and father may assist take care of his younger little one whereas he and his spouse had been each ailing with signs of coronavirus.

The PM stated in a speech on 18 March that “children should not be left with older grandparents, or older relatives, who may be particularly vulnerable or fall into some of the vulnerable groups”.

Former Conservative MP David Liddington, who was de facto deputy PM beneath Theresa Could, instructed BBC Newsnight: “There’s clearly serious questions that No 10 are going to have to address not least because the readiness of members of the public to follow government guidance more generally is going to be affected by this sort of story.”

Mr Johnson’s optimistic check for coronavirus was introduced on 27 March, and Downing Road stated on the time that Mr Cummings didn’t have signs.

Then, on 9 April, the PM’s official spokesman stated Mr Cummings was self-isolating with signs of the virus and was not again in No 10.